Coherer

Definitions

  • Coherer
    Coherer
  • Webster's Revised Unabridged Dictionary
    • n Coherer (Elec) Any device in which an imperfectly conducting contact between pieces of metal or other conductors loosely resting against each other is materially improved in conductivity by the influence of Hertzian waves; -- so called by Sir O. J. Lodge in 1894 on the assumption that the impact of the electic waves caused the loosely connected parts to cohere, or weld together, a condition easily destroyed by tapping. A common form of coherer as used in wireless telegraphy consists of a tube containing filings (usually a pinch of nickel and silver filings in equal parts) between terminal wires or plugs (called conductor plugs).
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Century Dictionary and Cyclopedia
    • n coherer In electricity, a tube filled with a conducting substance in powdered or granular form, as metal filings, which, when struck by an electric wave, as that sent out from a wireless telegraph station, decreases in electrical resistance, probably by the particles making a better contact with each other, and so is used to discover very minute electric waves, as in wireless telegraphy. After the passing of the electric wave the resistance of the coherer usually remains low, but it rises again when the tube is tapped.
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Chambers's Twentieth Century Dictionary
    • n Coherer an apparatus for the reception of the waves in 'wireless' telegraphy
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Etymology

Chambers's Twentieth Century Dictionary
L. cohærēre, cohæsum, co-, together, and hærēre, to stick.

Usage

In literature:

For a few moments she was utterly unable to give a coherent account of what had happened at Five Oaks.
"Tom Slade" by Percy K. Fitzhugh
Be coherent for a couple of seconds.
"The Little Warrior" by P. G. Wodehouse
Their putty-and-pasteboard fantasies did not long survive the Honorable William Linder's return to consciousness and coherence.
"Average Jones" by Samuel Hopkins Adams
The principal Poem in this little collection (Clifton Grove) is, he fears, deficient in numbers and harmonious coherency of parts.
"The Poetical Works of Henry Kirke White" by Henry Kirke White
Of that extraordinary place I shall not attempt to speak with any order or indeed with any coherence.
"A Passionate Pilgrim" by Henry James
I can't speak coherently.
"The Possessed" by Fyodor Dostoevsky
Then her listener became aware that she had achieved coherence.
"The Sturdy Oak" by Samuel Merwin, et al.
He could never be relied upon in any coherent practical plan of campaign.
"Marse Henry, Complete" by Henry Watterson
Their styles are separate, not cohering in a column nor projecting as in the climbing rose.
"Wild Flowers Worth Knowing" by Neltje Blanchan
His life would lose all purpose, all coherence, all flavor and zest.
"Bad Medicine" by Robert Sheckley
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In poetry:

For borne away in deadened air
May go the sudden shut of loss
Round something nearly at an end,
And what cohered in it across
The years, the unique random blend
Of families and fashions, there
"Ambulances" by Philip Larkin
I swear I think there is nothing but immortality!
That the exquisite scheme is for it, and the nebulous float is for
it, and the cohering is for it;
And all preparation is for it! and identity is for it! and life and
materials are altogether for it!
"To Think Of Time" by Walt Whitman

In news:

Syrian Opposition Finds Some Coherence .
Fitch's Riley: Coherence Needed After Italy's 2013 Elections.
Coherence In the Editorial Suites.
Government lacks coherent policy for religious time off, report finds.
Yahoo CEO says focused, coherent mobile strategy top priority.
Is that why so many of them lack coherent corrections policies.
With increased production value and coherent construction, Cobra Juicy represents a designer drug compared to Black Moth Super Rainbow's back catalog of LSD-soaked synth pop.
Brown fails to make consistent, coherent arguments to state voters about why they should back his tax measure.
Lacking a coherent message, it seems to me a hodge-podge of malcontents unhappy with their plot in life and with way too much time on their hands.
The visible indicators are perfectly obvious — loss of coordination, unable to articulate and an inability to think coherently.
Coherent Technology Enables the Seamless Upgrade to 100 Gb/s.
WASHINGTON (AP) — A panel of outside experts says NASA is adrift without a coherent vision for where it should be going.
Today's movies are often filled with paranoia , and sometimes they get too schizophrenic for coherence or comfort.
Bourbon Street is a haven for bachelorette parties, anniversaries, birthday celebrations and just about any other reason to party beyond coherence.
(The leaves dry out in the oven, which some see as a detriment—but they also cohere to the cheese and sauce that way, which I see as an advantage.
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In science:

A commutative ring R is coherent iff it is coherent as a R-module, or, equivalently, if every finitely generated ideal of R is finitely presented.
Double affine Hecke algebras and affine flag manifolds, I
For instance a Noetherian ring is coherent, the quotient of a coherent ring by a finitely generated ideal is a coherent ring and the localization of a coherent ring is again coherent.
Double affine Hecke algebras and affine flag manifolds, I
If the scheme X is coherent then an OX -module is coherent iff it is finitely presented, and we have f ∗ (C ohC ohC oh(Y )) ⊂ C ohC ohC oh(X ) for any morphism f : X → Y .
Double affine Hecke algebras and affine flag manifolds, I
If X is quasi-compact and coherent then any quasi-coherent OX -module is the direct colimit of a system of coherent OX -modules.
Double affine Hecke algebras and affine flag manifolds, I
Finally a good subscheme Y of a coherent scheme X is again coherent and the direct image of OY is a coherent OX -module.
Double affine Hecke algebras and affine flag manifolds, I
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